(CNN)Donald Trump's latest controversial comments are creating a constitutional stir, raising questions about the protections of the First and Second Amendments -- and whether a presidential candidate crossed a legal line.

Speaking at an event on Tuesday, Trump said:

"Hillary wants to abolish -- essentially abolish the Second Amendment. By the way, if she gets to pick, if she gets to pick her judges, nothing you can do, folks. Although the Second Amendment people, maybe there is, I don't know."

Many were quick to interpret the remarks as an incitement of violence against his Democratic rival, Hillary Clinton. But were the comments unlawful? Or just protected political hyperbole?

Danny Cevallos

The Supreme Court since 1969 has held that the freedoms of speech and press do not permit the government to criminalize comments by someone who advocates violence or breaking the law. There are some very important exceptions to this rule, but encouraging violence may actually be constitutionally protected speech.

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In the years since, courts have gone further, holding that political speech may not be punished "just because it makes it more likely that someone will be harmed at some unknown time in the future by an unrelated third party."

It sounds harsh, but the rationale is this: if the First Amendment protects speech advocating violence, then the First Amendment must also at least protect speech that makes violence somewhat more probable. Scary, but that's our constitution sometimes.

Naturally, there must be limitations on speech advocating violence. Aggressive speech is protected, according to the Supreme Court, unless it "is directed to inciting or producing imminent lawless action and is likely to incite or produce such action."

That's a helpful exception in theory, but in practice, it doesn't give us a lot of practical guidance. For starters, what exactly is "imminent" lawless action? Apparently there's a difference between "Let's riot right now!" and "let's riot...next October!"

"Now" is immediate, which in turn is "imminent," and not protected. On the other hand, something happening a year from now is probably not "imminent." This exercise in absurdity could go on forever -- what about something in the middle? "Let's riot in a fortnight!" Or something purely contingent? "Let's riot if -- and only if -- the Phillies win the World Series!"

"Imminence" is necessarily a function of the actual language, the surrounding facts, and the individual courts reviewing these cases.

Next, there's the "directed to" language in the exception; both must be satisfied to divest speech of its protections. "Directed to" means speech is designed to induce others to break the law. It's really a two-part exercise in linguistics: First, look at the speaker, and whether the utterance was intended as an order or a demand ("go riot, everyone!"), or if it was just an assertion of fact ("I love riots!"), or even a question ("should we riot?").

Second, you have to look at the effect of the utterance on the person who heard it. The hearer might have thought it was just a persuasive argument ("I now agree riots are good"), or he might have just been scared by the rhetoric ("I'm leaving; there's going to be a riot"). But he might also take it as an order to do something ("Okay, I'm convinced. I'll riot").

So, speech advocating violence may be protected, unless it is 1) "directed to" inciting 2) "imminent" unlawful action. If those elements are present -- whatever those elements actually are -- the speech is no longer protected.

Let's apply these principles to Trump's recent comments.

Start with the presumption that even speech encouraging violence is presumed protected, unless it is 1) "directed to" inciting 2) "imminent" unlawful action.

First, the "directed to" prong. Is there an order or a request by Trump directing violence? Only Trump's second sentence could potentially direct anyone to do anything. Many have understandably interpreted it as encouraging gun owners to shoot Hillary Clinton.

But Trump falls far short of giving an order or requesting action; instead, his words vaguely suggest what others' options are, should certain events occur. Reasonable minds have already differed on this interpretation, though. Trump also sprinkles in words like "maybe", punctuated with a non-committal "I don't know." Also, to conclude the statement directs violence requires an additional assumption that "Second Amendment People" only "do" things with their guns, and that's the only thing they "do."

As much as critics have a strong argument that Trump was making a not-so-subtle suggestion, Trump's statement probably does not meet the Supreme Court's test for "directing" unlawful action.

Yet even assuming Trump's statement was speech encouraging unlawful violence, it might not meet the "imminent" prong, either. "If [Hillary] gets to pick her judges" can only mean a future contingent event -- one that is not just uncertain, but that Trump himself has insisted will not happen. Trump believes more than anyone that he's "going to win so big."

Should Hillary in fact be elected president, the earliest she could "pick her judges" would be some time well into in 2017. It seems that Trump's statement could not incite imminent action.

The exception requires both prongs to apply: It must be directed to imminent unlawful action. It appears Trump's statement doesn't meet either.

In one Supreme Court case, a protester was at a public rally in 1966 speaking about his opposition to the Vietnam War and the draft. He was convicted under a presidential threat statute for saying: "If they ever make me carry a rifle, the first man I want to get in my sights is [President Lyndon Johnson]."

The Supreme Court reversed, holding that the defendant had not made a "true 'threat,'" but had rather engaged in mere "political hyperbole." Moreover, "debate on public issues should be uninhibited, robust, and wide-open, and it may well include vehement, caustic, and sometimes unpleasantly sharp attacks on government and public officials."

To the court, the "language of the political arena . . . is often vituperative, abusive, and inexact, [and that the only crime committed] here was a kind of very crude offensive method of stating a political opposition to the President."

Sound familiar?

Perhaps even more telling is the procedural path this case took: The Supreme Court reversed where two lower courts had convicted. If nothing else, even to learned judges, true threats are in the eye of the beholder.

Some legal scholars have observed that Trump has engaged in "stochastic terrorism," using language and other forms of communication "to incite random actors to carry out violent or terrorist acts that are statistically predictable but individually unpredictable."

It's scary, and probably true. Speech like this could someday influence some violence somewhere, especially in the aggregate, with so many other disparaging comments about political opponents. It's hard to predict or measure the effect with any certainty.

It's not a good idea for presidential candidates to talk this way. But it's likely not criminal speech; it is protected because it doesn't direct others to imminent unlawful action. This is apparently the political dialogue we, and the Supreme Court, have chosen to protect.

If you don't agree with Supreme Court justices and the presidents who pick them, there's nothing you can do folks ... although the people who get out and vote for presidents, maybe there is, I don't know.